<div style="color:Black;background-color:White;"><pre>
<span style="color:Green;">/*
more
than
one
line
comment
*/</span>

<span style="color:Green;">// single line comment</span>

<span style="color:Green;"># a different single line comment</span>

$foo = <span style="color:#A31515;">'a string'</span>

$foo2 = <span style="color:#A31515;">&quot;a string&quot;</span>

<span style="color:Green;">//$foo = 'a string'</span>

<span style="color:Green;">//$foo2 = &quot;a string&quot;</span>

$foo3 = <span style="color:#A31515;">&quot;a string&quot;</span> <span style="color:Green;">// a comment</span>

<span style="color:Green;">/* Incorrect Method: */</span>
<span style="color:Blue;">if</span>($a &gt; $b):
    <span style="color:Blue;">echo</span> $a.<span style="color:#A31515;">&quot; is greater than &quot;</span>.$b;
<span style="color:Blue;">else</span> <span style="color:Blue;">if</span>($a == $b): <span style="color:Green;">// Will not compile.</span>
    <span style="color:Blue;">echo</span> <span style="color:#A31515;">&quot;The above line causes a parse error.&quot;</span>;
<span style="color:Blue;">endif</span>;

<span style="color:Green;">/* Correct Method: */</span>
<span style="color:Blue;">if</span>($a &gt; $b):
    <span style="color:Blue;">echo</span> $a.<span style="color:#A31515;">&quot; is greater than &quot;</span>.$b;
<span style="color:Blue;">elseif</span>($a == $b): <span style="color:Green;">// Note the combination of the words.</span>
    <span style="color:Blue;">echo</span> $a.<span style="color:#A31515;">&quot; equals &quot;</span>.$b;
<span style="color:Blue;">else</span>:
    <span style="color:Blue;">echo</span> $a.<span style="color:#A31515;">&quot; is neither greater than or equal to &quot;</span>.$b;
<span style="color:Blue;">endif</span>;

&lt;?php
$<span style="color:Blue;">file</span> = fopen(<span style="color:#A31515;">&quot;welcome.txt&quot;</span>, <span style="color:#A31515;">&quot;r&quot;</span>) <span style="color:Blue;">or</span> <span style="color:Blue;">exit</span>(<span style="color:#A31515;">&quot;Unable to open file!&quot;</span>);
<span style="color:Green;">//Output a line of the file until the end is reached</span>

<span style="color:Green;">/* single line comment */</span>

<span style="color:Blue;">echo</span> <span style="color:#A31515;">&quot;&lt;table width=\&quot;175\&quot; border=\&quot;1\&quot; class=\&quot;Table1\&quot;&gt;\n&quot;</span>;
$regex = <span style="color:#A31515;">'/(?:(&quot;)|(?:\'))((?(1)[^&quot;]+|[^\']+))(?(1)&quot;|\')/'</span>;

<span style="color:Blue;">while</span>(!feof($<span style="color:Blue;">file</span>))
 {
 <span style="color:Blue;">echo</span> fgets($<span style="color:Blue;">file</span>). <span style="color:#A31515;">&quot;&lt;br /&gt;&quot;</span>;
<span style="color:Green;">/* single line comment */</span>
 }
           <span style="color:Green;">/*multi line style
            * Second line
            * third line
            * fourth line
           */</span>
<span style="color:Blue;">fclose</span>($<span style="color:Blue;">file</span>);
<span style="color:Blue;">mysqli_fetch_object</span>())
<span style="color:Blue;">and</span>
<span style="color:Blue;">__LINE__</span> 
<span style="color:Blue;">class</span> 
<span style="color:Blue;">die</span>() 
<span style="color:Blue;">empty</span>() 
<span style="color:Blue;">endswitch</span> 
<span style="color:Blue;">for</span> 
<span style="color:Blue;">include</span>() 
<span style="color:Blue;">print</span>() 
<span style="color:Blue;">switch</span> 
<span style="color:Blue;">__FUNCTION__</span> 
<span style="color:Blue;">interface</span>
<span style="color:Blue;">protected</span>
<span style="color:Blue;">throw</span>
<span style="color:Blue;">or</span> 
<span style="color:Blue;">array</span>() 
<span style="color:Blue;">const</span> 
<span style="color:Blue;">do</span> 
<span style="color:Blue;">enddeclare</span> 
<span style="color:Blue;">endwhile</span> 
<span style="color:Blue;">foreach</span> 
<span style="color:Blue;">include_once</span>() 
<span style="color:Blue;">require</span>() 
<span style="color:Blue;">unset</span>() 
<span style="color:Blue;">__CLASS__</span> 
<span style="color:Blue;">implements</span>
<span style="color:Blue;">abstract</span>
<span style="color:Blue;">cfunction</span>
<span style="color:Blue;">namespace</span>
<span style="color:Blue;">xor</span> 
<span style="color:Blue;">as</span> 
<span style="color:Blue;">continue</span> 
<span style="color:Blue;">echo</span>() 
<span style="color:Blue;">endfor</span> 
<span style="color:Blue;">eval</span>() 
<span style="color:Blue;">function</span> 
<span style="color:Blue;">isset</span>() 
<span style="color:Blue;">require_once</span>() 
<span style="color:Blue;">use</span> 
<span style="color:Blue;">__METHOD__</span> 
<span style="color:Blue;">clone</span>
<span style="color:Blue;">old_function</span>
<span style="color:Blue;">goto</span>
<span style="color:Blue;">__FILE__</span> 
<span style="color:Blue;">break</span> 
<span style="color:Blue;">declare</span> 
<span style="color:Blue;">else</span> 
<span style="color:Blue;">endforeach</span> 
<span style="color:Blue;">exit</span>() 
<span style="color:Blue;">global</span> 
<span style="color:Blue;">list</span>() 
<span style="color:Blue;">return</span>() 
<span style="color:Blue;">var</span> 
<span style="color:Blue;">final</span>
<span style="color:Blue;">public</span>
<span style="color:Blue;">try</span>
this
<span style="color:Blue;">exception</span>
<span style="color:Blue;">case</span> 
<span style="color:Blue;">default</span> 
<span style="color:Blue;">elseif</span> 
<span style="color:Blue;">endif</span> 
<span style="color:Blue;">extends</span> 
<span style="color:Blue;">if</span> 
<span style="color:Blue;">new</span> 
<span style="color:Blue;">static</span> 
<span style="color:Blue;">while</span> 
<span style="color:Blue;">php_user_filter</span>
<span style="color:Blue;">private</span>
<span style="color:Blue;">catch</span>
<span style="color:Blue;">final</span>
?&gt; 

</pre></div>